**Iterating over a list in a function**

For the life of my, i don't understand what I'm doing wrong. I have the correct output displaying.

Code behaves correctly but does not pass the marking criteria.

```
n = [3, 5, 7]
def total(numbers):
result = 0
for i in range(len(n)):
result += n[i]
return result
print total(n)
```